1. Field of the Invention
The present invention relates to an image taking apparatus, and more particularly, to an image taking apparatus capable of correcting a shake of an image, an apparatus and method for processing an image to correct a shake of an image, and a computer program for implementing the method on a computer.
2. Description of the Related Art
In recent years, an image taking apparatus such as a digital still camera, a digital video camera, and a camera usable as both a still camera and a motion camera has become increasingly popular, and a great improvement in performance thereof has been achieved. However, when an image of a subject is taken by an image taking apparatus held in a hand, two types of shakes can occur. One is a shake of the image taking apparatus, and the other is a shake of the subject.
One technique to detect such a shake is to use a sensor such as a vibration sensor, a velocity sensor, an acceleration sensor, or a gravitational sensor to detect the shake. Another technique is to detect a motion vector by image processing.
The blur of the image taken by the image taking apparatus due to the shake can be prevented or suppressed by moving the position of the image in a direction opposite to a shake direction in accordance with the result of detection of the shake. One method of preventing/suppressing the shake is to electronically compensate for the shake by shifting a reading address of an image sensor shifting a writing/reading address of an image memory. Another method is to optically compensate for the shake by shifting/tilting a shake compensation lens, deforming/tilting a shake compensation prism, or shifting an image sensor.
For example, it has been proposed to sample a shake signal output from a shake sensor in synchronization with a sample timing signal depending on a shutter speed supplied from a timing generator, and control a reading address of an image signal output from an image sensor in accordance with the sampled shake signal (for example, see Japanese Unexamined Patent Application Publication No. 05-316404).